Fast detachable polishing plate mechanism

ABSTRACT

The present invention provides a fast detachable polishing plate mechanism. The fast detachable polishing plate mechanism includes a polishing plate and a rod. The polishing plate has an adhesion unit disposed on the lower surface of the polishing plate. The rod connects straightly to the upper surface of the polishing plate. The rod is divided into an upper section, a middle section and a lower section from top to bottom, and only the middle section has a thread. The present invention further provides a hand-held machine tool having a drive shaft. The drive shaft has a tapped hole. The fast detachable polishing plate mechanism is mounted to the hand-held machine tool through the rod being inserted to the tapped hole.

RELATED APPLICATIONS

The present application claims the priority of Taiwan Application No. 107212476, filed on Sep. 12, 2018, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to polishing plates, and more specifically, to a fast detachable polishing plate which is easy to install and disassemble in a sander.

2. Description of Related Art

Sanders are quite common in the industry and are mainly used to polish objects. The sander is based on a motor and is operated with various types of sanding elements. In practice, different sanding components are replaced depending on the user's needs, and they are often required to be installed or removed. At present, some types of sanding machines installed on the market are fixed components, which cannot be removed and replaced. Some types of sanding components installed in the sander can be replaced at will, but it is inconvenient to install or disassemble.

Please refer to FIG. 1. FIG. 1 is a schematic view showing the joint structure of a conventional polishing device. The polishing device is mounted on the sander by a joint structure, which may be a rod 11. As shown in FIG. 1, the surface of the rod 11 has a thread 111 which extends along the surface of the rod 11 to the end face of the rod 11. The sander has a threaded hole 10 with an internal thread 101 therein. Generally, when the rod 11 is inserted into the tapped hole 10, the thread 111 of the rod 11 needs to be aligned with the internal thread 101 of the tapped hole 10 to fasten the rod 11 into the tapped hole 10. If the user is too careless or eager to turn the rod 11 into the tapped hole 10, the thread 111 of the end face of the rod 11 may be damaged, thereby destroying the stability of the overall structure of the rod 11 and the tapped hole 10.

Thus, there is an urgent need to develop a joint structure which is capable of disassembling quickly between the sander and the sanding components.

SUMMARY OF THE INVENTION

In order to solve the foregoing problems of the prior art, the present invention provides a fast detachable polishing plate mechanism, which comprises: a polishing plate having an adhesion unit disposed on the lower surface thereof; and a rod connected straightly to the upper surface of the polishing plate, wherein the rod is divided into an upper section, a middle section and a lower section from top to bottom, and only the middle section has a thread.

In an embodiment, the fast detachable polishing plate mechanism further comprises a grinding unit fixed to the surface of the polishing plate through the adhesion unit.

In an embodiment, the grinding unit includes a sponge or a sandpaper.

In an embodiment, the adhesion unit includes a touch fastener.

In an embodiment, the end face of the upper section of the rod is cylindrical, spherical, chamfered or tapered.

The present invention provides a hand-held machine tool, which comprises a drive shaft having a tapped hole used for jointing to the rod of the fast detachable polishing plate mechanism described above.

Compared with the prior art, the fast detachable polishing plate mechanism provided by the present invention is easily jointed to the polishing device through the upper section of the rod being quickly aligned with and inserted into the tapped hole of the polishing device. Then, the thread at the middle section of the rod is coupled to the female thread in the tapped hole so that the polishing plate can be fixed to the polishing device. The fast detachable polishing plate mechanism of the present invention has the advantages of easy disassembly and quick loading. It is convenient for the user to replace the grinding components with different grinding units.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a conventional polishing plate mechanism.

FIG. 2 is a schematic view of the fast detachable polishing plate mechanism of the present invention.

FIG. 3 is a schematic view of the hand-held machine tool of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present invention is described by the following specific embodiments. Those with ordinary skills in the arts can readily understand other advantages and functions of the present invention after reading the disclosure of this specification. The present disclosure may also be practiced or applied with other different implementations. Based on different contexts and applications, the various details in this specification can be modified and changed without departing from the spirit of the present disclosure.

It should be noted that the structures, ratios, sizes shown in the drawings appended to this specification are to be construed in conjunction with the disclosure of this specification in order to facilitate understanding of those skilled in the art. They are not meant, in any ways, to limit the implementations of the present invention, and therefore have no substantial technical meaning. Without affecting the effects created and objectives achieved by the present invention, any modifications, changes or adjustments to the structures, ratio relationships or sizes, are to be construed as fall within the range covered by the technical contents disclosed herein. Meanwhile, terms, such as “upper”, “inner”, “external”, “bottom”, “one”, “a” and the like, are for illustrative purposes only, and are not meant to limit the range implementable by the present invention. Any changes or adjustments made to their relative relationships, without modifying the substantial technical contents, are also to be construed as within the range implementable by the present invention.

Please refer to FIG. 2. FIG. 2 is a schematic view of the fast detachable polishing plate mechanism of the present invention. The fast detachable polishing plate mechanism comprises a polishing plate 21 and a rod 22. The polishing plate 21 is a tool used for contacting objects to be polished. The polishing plate 21 has an adhesion unit 211 disposed on the lower surface thereof. The rod 22 connected straightly to the upper surface of the polishing plate 21. The rod 22 is divided into an upper section 223, a middle section 222 and a lower section 221 from top to bottom. The technical feature of the present invention is that the middle section 222 of the rod 22 has a thread. More specifically, the lower section 221 of the rod 22 is inserted onto the upper surface of the polishing plate 21, and the middle section 222 of the rod 22 is adjacent to the upper edge of the lower section 221, and the upper section 223 of the rod 22 is adjacent to the upper edge of the middle section 222. The middle section 222 of the rod 22 has a thread 2221 on its surface, and the lower section 221 and the upper section 223 have no threads on their surface.

Since the surfaces of the lower section 221 and the upper section 223 of the rod 22 are not provided with threads, the upper section 223 is only a cylindrical structure easily to be inserted into the tapped hole 20 by guiding the user. The user can directly insert the upper section 223 into the tapped hole 20 of the sander without worrying about whether the internal thread 201 in the tapped hole 20 is aligned. The middle section 222 of the rod 22 is inserted into the tapped hole along the upper section 223. At the same time, the thread 2221 on the surface of the middle section 222 is automatically aligned with the internal thread 201 of the tapped hole 20. After that, the user applies the force to rotate the rod 22 so that the rod 22 is coupled to the tapped hole 20.

Besides, the improve structure of the lower section 221 can make the user easily disassemble the polishing plate. It is not easy for the user to disassemble the conventional structure of FIG. 1 due to the excessive friction between the threads of the tapped hole 10 and the rod 11. Specifically, the locking of the rod 11 and the tapped hole 10 is based on the friction force of the engagement between the external thread of the rod 11 with the internal thread of the tapped hole 10. In the conventional structure shown in FIG. 1, when the rod 11 is inserted into the tapped hole 10 and is applied a torque to be locked, the thread 111 of the rod 11 extends up to the opening of the tapped hole 10. Moreover, the thread 1111, 1112 at the upper and lower ends of the rod 11 in the conventional structure often have an incomplete angle due to the processing manner, thereby increasing the degree of fastening during the engagement of the rod 11 and the tapped hole 10. In the improved structure of the present invention shown in FIG. 2, the thread 2221 of the rod 22 is disposed only in the middle section 222. When the rod 22 is inserted into the tapped hole 20, the portion at the rod 22 corresponding to the opening of the tapped hole 20 is the lower portion 221 which has no threads. Therefore, the opening of the tapped hole 20 is a free section which exists no friction caused by the engagement between the internal thread and external thread or the incomplete angle of the threads. In other words, the contact area when the internal threads and the external threads are frictionally engaged in the improved structure of the present invention is smaller than the contact area in the conventional structure. The frictional force is relatively small so the fast detachable polishing plate mechanism is naturally easier to be disassembled.

In an embodiment of the present invention, the fast detachable polishing plate mechanism further comprises a grinding unit 23. The grinding unit 23 is fixed to the surface of the polishing plate 21 through the adhesion unit 211. The adhesion unit 211 can be, for example, a touch fastener. The grinding unit 23 includes, for example, a sponge or sandpaper, adhered to the polishing plate 21 via a touch fastener.

In the preferred embodiment of the present invention, the shape of the end surface B of the upper portion 223 of the rod 22 is planar. In other embodiments, the shape of the end surface B may be other shapes, such as a cylindrical, a spherical, a chamfered, or a tapered. Further, the end face B of the upper section 223 of the rod 22 cannot contact the bottom A of the tapped hole 20, thereby avoiding an increase in friction.

Please refer to FIG. 2 and FIG. 3 together. FIG. 3 is a schematic view of the hand-held machine tool of the present invention. The present invention further provides a handed machine tool 3 comprising a drive shaft and the fast detachable polishing plate mechanism described in the above. The cross-sectional view of the drive shaft can be referred to the structure indicated by the slanted line in FIG. 2. The lower surface of the draft shaft has a tapped hole 20 having an internal thread 201 on the hole wall to facilitate engaging with the rod 22 of the fast detachable polishing plate mechanism.

The fast detachable polishing plate mechanism of the present invention is improved by the upper and lower sections of the rod connected to the sander being provided without threads, so that the rod can be quickly aligned when inserted in the tapped holes. It is more convenient to disassemble, making it easier for users to replace various grinding components.

The above embodiments are only used to illustrate the principles of the present invention, and should not be construed as to limit the present invention in any way. The above embodiments can be modified by those with ordinary skill in the art without departing from the scope of the present invention as defined in the following appended claims. 

What is claimed is:
 1. A fast detachable polishing plate mechanism, comprising: a polishing plate having an adhesion unit disposed on a lower surface thereof; and a rod connected straightly to an upper surface of the polishing plate, wherein the rod is divided into an upper section, a middle section and a lower section from top to bottom, and only the middle section has a thread.
 2. The fast detachable polishing plate mechanism of claim 1, further comprising a grinding unit fixed to the lower surface of the polishing plate through the adhesion unit.
 3. The fast detachable polishing plate mechanism of claim 2, wherein the grinding unit includes a sponge or a sandpaper.
 4. The fast detachable polishing plate mechanism of claim 1, wherein the adhesion unit includes a touch fastener.
 5. The fast detachable polishing plate mechanism of claim 1, wherein the end face of the upper section of the rod is cylindrical, spherical, chamfered or tapered.
 6. A hand-held machine tool, including: the fast detachable polishing plate mechanism of any one of claim 1; and a drive shaft having a tapped hole used for jointing to the rod of the fast detachable polishing plate mechanism. 